By SARAH DiLORENZO and JOHANNA DECORSE
TOULOUSE, France (AP) - Riot police set off explosions outside an apartment building early Thursday in an effort to force the surrender of a gunman who boasted of bringing France "to its knees" with an al-Qaida-linked terror spree that killed seven people.
Hundreds of heavily armed police, some in body armor, surrounded the five-story building in Toulouse where the 24-year-old suspect, Mohamed Merah, had been holed up since the pre-dawn hours of Wednesday.
As midnight approached, three explosions were heard and orange flashes lit up the night sky near the building. An Interior Ministry official said the suspect had gone back on a previous pledge to turn himself in _ and that police blew up the shutters outside the apartment window to pressure him to surrender.
Sporadic blasts and bursts of gunfire rang out throughout the night, though officials insisted no full-out assault was under way. "It's not as simple as that. We are waiting," the Toulouse prosecutor, Michel Valet, told The Associated Press.
Authorities said the shooter, a French citizen of Algerian descent, had been to Afghanistan and Pakistan, where he claimed to have received training from al-Qaida.
They said he told negotiators he killed a rabbi and three young children at a Jewish school on Monday and three French paratroopers last week to avenge the deaths of Palestinian children and to protest the French army's involvement in Afghanistan, as well as a government ban last year on face-covering Islamic veils.
"He has no regrets, except not having more time to kill more people and he boasts that he has brought France to its knees," Paris Prosecutor Francois Molins told a news conference.
French authorities _ like others in Europe _ have long been concerned about "lone-wolf" attacks by young, Internet-savvy militants who self-radicalize online since they are harder to find and track. Still, it was the first time a radical Islamic motive has been ascribed to killings in France in years.
Merah espoused a radical brand of Islam and had been to the Afghanistan-Pakistan region twice and to the Pakistani militant stronghold of Waziristan for training, Molins said.
He said the suspect had plans to kill another soldier, prompting the police raid.
The standoff began after a police attempt at around 3 a.m. Wednesday to detain Merah erupted into a firefight. Two police were wounded, triggering on-and-off negotiations with the suspect that lasted into the night.
As darkness fell, police cut electricity and gas to the building, then quietly closed in to wait out the suspect.
Authorities were "counting on his great fatigue and weakening," said Didier Martinez of the SGP police union, adding the siege could go on for hours. Street lights were also cut, making Merah more visible to officers with night vision goggles in case of an assault.
The gunman's brother and mother were detained early Wednesday. Molins said the 29-year-old brother, Abdelkader, had been implicated in a 2007 network that sent militant fighters to Iraq, but was never charged.
The siege was part of France's biggest manhunt since a wave of terrorist attacks in the 1990s by Algerian extremists. The chase began after France's worst-ever school shooting Monday and two previous attacks on paratroopers beginning March 11, killings that have horrified the country and frozen campaigning for the French presidential election next month.
French President Nicolas Sarkozy, who has played up nationalist themes in his bid for a second term, vowed to defend France.
"Terrorism will not be able to fracture our national community," Sarkozy declared Wednesday on national television before heading to funeral services for the two paratroopers killed and another injured last week in Montauban, near Toulouse.
The suspect repeatedly promised to turn himself in, then halted negotiations. Cedric Delage, regional secretary for a police union, said police were prepared to storm the building if he did not surrender.
After bouts of deadly terrorist attacks in France in the 1980s and 1990s, France beefed up its legal arsenal _ now seen as one of the most effective in Western Europe and a reference for countries including the U.S. after the Sept. 11 attacks.
Sarkozy's office said President Barack Obama called him Wednesday to express condolences to the families of the victims and praise French police for tracking down the suspect. The statement said France and the United States are "more determined than ever to fight terrorist barbarity together."
In recent years, French counterterrorism officials have focused mainly on al-Qaida in the Islamic Maghreb, the North African affiliate of Osama bin Laden's network that has its roots in an insurgent group in Algeria, a former French colony.